High Prevalence of Obstructive Sleep-Disordered Breathing in Pediatric Patients With Turner Syndrome.

OBJECTIVE: Girls with Turner syndrome (TS) often have features that have been associated with obstructive sleep-disordered breathing (oSDB). However, little is known about oSDB in TS. Herein, we aimed to characterize oSDB in young patients with TS and identify associated risk factors. STUDY DESIGN: Retrospective cross-sectional study. SETTING: Tertiary care pediatric hospital. METHODS: We reviewed medical records for patients diagnosed with TS seen at our institution between October 1, 2007 and December 31, 2019 with the first outpatient visit before age 6 years. The prevalence of oSDB was compared to the general pediatric population with 1-sample binomial proportion tests. Clinical characteristics were compared between those diagnosed with oSDB and those without oSDB, and risk factors for oSDB were identified. RESULTS: Of 151 patients with TS, 73 (48%) were diagnosed with oSDB which is 4-fold higher than the general pediatric population (12%, P < 0.0001). In the multivariable model, adenoid, tonsillar, and inferior turbinate hypertrophy, birthweight, failure to thrive, and older age at the last clinic visit were all associated with increased odds for oSDB. CONCLUSION: Young children with TS have a high prevalence of oSDB and thus should be screened for oSDB. Polysomnography should be performed in those with associated risk factors and symptoms oSDB. Treatment of oSDB is imperative as individuals with TS are already at increased risk of behavioral problems, neurocognitive deficits, and growth impairment that may be worsened with oSDB.

ST2/MyD88 Deficiency Protects Mice against Acute Graft-versus-Host Disease and Spares Regulatory T Cells.

Acute graft-versus-host disease (aGVHD) hinders the efficacy of allogeneic hematopoietic cell transplantation (HCT). Plasma levels of soluble membrane-bound ST2 (ST2) are elevated in human and murine aGVHD and correlated to type 1 T cells response. ST2 signals through the adapter protein MyD88. The role of MyD88 in T cells during aGVHD has yet to be elucidated. We found that knocking out MyD88 in the donor T cells protected against aGVHD independent of IL-1R and TLR4 signaling in two murine HCT models. This protection was entirely driven by MyD88-/- CD4 T cells. Transplanting donor MyD88-/- conventional T cells (Tcons) with wild-type (WT) or MyD88-/- regulatory T cells (Tregs) lowered aGVHD severity and mortality. Transcriptome analysis of sorted MyD88-/- CD4 T cells from the intestine 10 d post-HCT showed lower levels of Il1rl1 (gene of ST2), Ifng, Csf2, Stat5, Batf, and Jak2 Transplanting donor ST2-/- Tcons with WT or ST2-/- Tregs showed a similar phenotype with what we observed when using donor MyD88-/- Tcons. Decreased ST2 was confirmed at the protein level with less secretion of soluble ST2 and more expression of ST2 compared with WT T cells. Our data suggest that Treg suppression from lack of MyD88 signaling in donor Tcons during alloreactivity uses the ST2 but not the IL-1R or TLR4 pathways, and ST2 represents a potential aGVHD therapeutic target sparing Tregs.